AT least 800 volunteers will be needed for the second and third phases of the trials of China's AIDS vaccine after the initial test results showed it to be safe and possibly effective, health officials said.

The second phase of clinical trials of China's AIDS vaccine would need at least 300 volunteers and the third phase at least 500, said Sang Guowei, director of the National Institute for the Control of Pharmaceutical and Biological Products.

The later trials would involve the participation of high-risk groups, said Chen Jie, deputy director of the Guangxi Regional Center for Disease Control and Prevention (CDC).

The first phase indicates China's first AIDS vaccine is safe, government officials said Friday.

"Forty-nine healthy people who received the injection showed no severe adverse reactions after 180 days, proving the vaccine was safe," said Zhang Wei, head of the pharmaceutical registration department of the State Food and Drug Administration.

"The recipients appeared immune to the HIV-1 virus 15 days after the injection, indicating the vaccine worked well in stimulating the body's immunity," he told a press conference Friday.

The results mark the end of the first phase of the clinical trials of the AIDS vaccine, which focused on the vaccine's safety.

The first phase was carried out in Nanning, capital of the Guangxi Zhuang Autonomous Region, on March 12 last year. The volunteers, 33 men and 16 women aged between 18 and 50, received the vaccine by Oct. 20.

The new vaccine must undergo three phases of clinical trials before going into production. The second phase will assess both safety and immunity of the vaccine while the third will target the protection it offers for high-risk groups.

By the end of 2005, China had recorded more than 140,000 people infected with HIV. Officials estimate that China has approximately 650,000 people living with HIV, including approximately 75,000 AIDS patients.

The total HIV infections in the world had exceeded 40 million and more than 30 million AIDS patients had died by the end of 2005, according to figures released by the World Health Organization (WHO) and the Joint United Nations Program on HIV/AIDS (UNAIDS).

Editor: Wing